The road actually goes straight through the middle of this roundabout, so the off/on is unnecessary.

I'm unsure if some local knowledge (I'm not from these parts) means that it might be quicker to go onto roundabout and off again, but GPS traces look like most folks go straight through. There is 2 sets of traffic lights, and potentially more slower moving traffic when heading straight on.

I don't see how you go about prodding routing information on the map editor, and the map itself looks fine.